REUTERS

At least 15 people, including six children, were killed Friday night when suspected militants set off a series of explosions and engaged cops in gunfire during a raid by Sri Lankan police in connection to the deadly Easter Sunday suicide bombings, authorities said.

Authorities told the AP they received a tip that members of the group associated with the coordinated terrorist bombings that killed more than 250 people last week were in a safe house near the town of Sammanthurai. When they arrived, militants “detonated three explosions and opened fire.”

The U.S. Department of State, citing possible secondary attacks, urged Americans to reconsider traveling to Sri Lanka and have ordered children of government workers to leave the country.

Most of the victims in the latest round of violence—which also included six men and three women—were killed in three bomb blasts that ripped apart the roof and one wall of the house, police said. One witness told CNN the explosion during the house “into fire.”

Police spokesman Ruwan Gunasekara told the AP that most the victims were “likely were militants” who blew themselves up in multiple suicide bombings. At least one civilian had been killed in the attack.

“A girl and a woman survived the explosion at the suspected safe house but were critically injured and being treated at a hospital,” Gunasekara said, who later revealed the two are related to the mastermind behind the bombings, Mohamed Hashim Mohamed Zahran.

Friday’s explosive confrontation comes amid a nationwide security crackdown widespread fear over the Easter Sunday bomb blasts at three churches and four hotels across Sri Lanka that left hundreds more injured in one of the worst bouts of violence in the island nation has seen since the civil war. Since the explosion which was claimed by ISIS as a response to mass killing of muslims in New Zealand, Sri Lankan police have warned civilians of possible further attacks.

“These vile attacks are a stark reminder of why the United States remains resolved in our fight to defeat terrorism” U.S. Secretary of State Mike Pompeo said in a statement after the Sunday attacks, confirming that “several Americans” had also been killed.

Sri Lankan police have also began conducting raids and police curfews that have shut down areas of eastern Sri Lanka, while Catholic leaders announced last week Sunday Masses will be canceled “indefinitely.”

Earlier on Friday, during a series of raids a few miles from the shootout, authorities seized a large cache of explosives, including 100,000 ball bearings, ISIS uniforms, and black Islamic State-style flags.

Sri Lankan President Maithripala Sirisena said Friday the new security measures, which he said were being used to identify and track people, have led to the arrest of 70 individuals with ISIS ties and has tracked another 70 suspects still at large.

“We had to declare an emergency situation to suppress terrorists and ensure a peaceful environment in the country,” the president said, defending the controversial methods that were also used during the Sri Lankran the civil war. “Every household in the country will be checked and lists of all residents made to ensure that no unknown person can live anywhere,” he vowed.

On Saturday, Maithripala Sirisena also requested for the police chief to step down following the suicide bombings for not sharing the advance warnings of the attacks on the island country, according to Reuters.

As previously reported by The Daily Beast, a Sri Lankan police official had alerted security officials in an advisory ten days ago before the attack about a threat on churches. The document, which was reviewed by The Daily Beast and is written in Sinhala, but is dated April 11 and clearly states in English in all caps, “Information of an alleged plan attack.” On Saturday, the AP reported the Indian Police also stumbled upon a detailed plot for the attack and altered Sri Lankan officials two weeks before the attack, but went unacknowledged.

The Defense secretary Hemesiri Fernando resigned earlier in the week for his role in why the warnings went unheeded, the inspector general of police Pujith Jayasundara has been holding on, until they find the suspects.

“He has refused to resign despite the president’s request,” one source told Reuters, adding that under the Sri Lanka constitution, only parliament can remove the police chief.